RUI: Innovative Determination of Phase Diagrams of Green Surfactants in Water and Ionic Liquids

该项目由实验物理化学计划支持，采用了一种新的方法来更快，更准确地确定一类重要的“绿色”表面活性剂在各种溶剂中的行为。 被称为烷基葡糖苷的表面活性剂被认为是“绿色”的，因为它们来源于天然存在的和可再生的资源，并且在很大程度上是环境和生理上良性的。 根据温度和溶液中表面活性剂的浓度，烷基葡糖苷组装成各种聚集体，如球形胶束和层状双层。我们的方法监测的荧光信号的染料，被纳入在溶剂-表面活性剂的混合物在非常低的浓度。 染料对其化学环境敏感，并产生反映存在的聚集体性质的独特信号。 这种技术的一个重要优点是，在不同的表面活性剂聚集体中的染料的荧光信号是相互独立的，因此，从共存的聚集体的信号可以同时检测。信号可以唯一地识别存在的聚集体的事实赋予该技术其新奇和力量。 将制备相图以说明作为浓度和温度的函数存在的聚集体。由于糖苷表面活性剂的所有实际和商业应用都严重依赖于表面活性剂相图的知识，因此该项目将提供准确和完整的信息，以便能够制备特定的骨料。 这个项目的一个特别有趣的方面是构建表面活性剂在水中的相图，然后将其与相同表面活性剂在离子液体中的相图进行比较。由于离子液体中表面活性剂行为的研究是一个相对未开发的领域，我们的研究在离子液体中的葡萄糖苷将作出重大贡献，这些绿色溶剂系统中的表面活性剂的现有文献。 由于准确的相图的可用性对从材料到生物化学的许多学科都很重要，因此该项目具有广泛的跨学科影响的潜力。 此外，这些调查的一个重要目标是培养有才华的本科生在研究生学习或工业生产职业的研究方法。 该项目将继续展示和提高有效的合作学生-教师研究的可行性，在共同主要研究者的实验室，主要是本科院校，导致同行评审的期刊和演示文稿在科学场所的出版物。

This project supported by the Experimental Physical Chemistry Program employs a new approach to more quickly and accurately determine the behavior of an important class of "green" surfactants in various solvents. The surfactants known as alkyl glucosides are considered "green" as they are derived from naturally occurring and renewable resources and are largely environmentally and physiologically benign. Depending on the temperature and the surfactant concentration in solution, alkyl glucosides assemble into a variety of aggregates such as spherical micelles and lamellar bilayers. Our approach monitors the fluorescence signal of a dye that is incorporated in the solvent-surfactant mixtures at very low concentrations. The dye is sensitive to its chemical environment and yields a unique signal that reflects the nature of the aggregate(s) present. One important advantage of this technique is that the fluorescence signals of the dye in different surfactant aggregates are independent of each other, and thus the signals from coexisting aggregates can be detected simultaneously. The fact that the signals can uniquely identify the aggregates present gives this technique its novelty and power. Phase diagrams will be prepared to illustrate the aggregates present as a function of concentration and temperature. As all of the practical and commercial applications of glucoside surfactants depend critically on knowledge of surfactant phase diagrams, this project will provide accurate and complete information to enable preparation of specific aggregates. A particularly intriguing aspect of this project is to construct and then compare the phase diagrams of the surfactants in water with the phase diagrams of the same surfactants in ionic liquids. As the study of surfactant behavior in ionic liquids is a relatively unexplored area, our investigations of the glucosides in ionic liquids will make a significant contribution to the available literature on surfactants in these green solvent systems. Since the availability of accurate phase diagrams is important to many disciplines from materials to biochemistry, this project has the potential for broad interdisciplinary impact. Furthermore, an important objective of these investigations is the training of talented undergraduate students in the methods of research for productive careers in graduate studies or industry. The project will continue to demonstrate and enhance the feasibility of effective collaborative student-faculty research in the co-principal investigators' laboratories at a primarily undergraduate institution leading to publications in peer-reviewed journals and presentations at scientific venues.